1. Field of the Invention
This invention relates to a novel device and system forming part of a phonograph pickup cartridge or otherwise attached to a tone arm of the phonograph. More particularly, it relates to such a device and system of improved construction which directs light at a record from a location near the cartridge or stylus in order to increase the accuracy of cueing the stylus on the record.
2. Description of the Prior Art
It is known in the prior art to facilitate cueing a phonograph stylus or needle on a phonograph record by illuminating the record from an incandescent lamp or similar light source attached to or built into the tone arm of the photograph. Such illumination systems are shown, for example, in the following issued U.S. Patents: U.S. Pat. No. 1,193,825, issued Aug. 8, 1916 to Roop; U.S. Pat. No. 2,309,060, issued Jan. 19, 1943 to Glaser; U.S. Pat. No. 2,949,529, issued Aug. 16, 1960 to Ogawa and U.S. Pat. No. 4,079,944, issued Mar. 21, 1978 to Durley III et al. Construction of a magnetic phonograph pickup cartridge is further described in U.S. Pat. No. 3,846,592, issued Nov. 5, 1974 to Stanton. While the concept of providing such illumination has therefore been known for many years, such illumination systems have not achieved commercial acceptance. The prior art systems have been bulky, built into the tone arm, too heavy for use with present day low force tone arms, or otherwise unsuited for use with present day tone arm and cartridge construction. As a result, they cannot be retrofit in existing phonographs, and their incorporation as original equipment in phonographs would require substantial changes in current phonograph designs.